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| author | Brooke Basile <brookebasile@gmail.com> | 2020-09-11 03:14:27 -0400 |
|---|---|---|
| committer | Kalle Valo <kvalo@codeaurora.org> | 2020-09-21 16:05:43 +0300 |
| commit | 03fb92a432ea5abe5909bca1455b7e44a9380480 (patch) | |
| tree | 0b366da59ec687f96d5c591c3a27dd90e2f9dcac /drivers/net/wireless/ath/ath9k/hif_usb.c | |
| parent | 5a6bd84f815485800699f55c78f690b2ed35f0c5 (diff) | |
| download | linux-03fb92a432ea5abe5909bca1455b7e44a9380480.tar.gz linux-03fb92a432ea5abe5909bca1455b7e44a9380480.tar.bz2 linux-03fb92a432ea5abe5909bca1455b7e44a9380480.zip | |
ath9k: hif_usb: fix race condition between usb_get_urb() and usb_kill_anchored_urbs()
Calls to usb_kill_anchored_urbs() after usb_kill_urb() on multiprocessor
systems create a race condition in which usb_kill_anchored_urbs() deallocates
the URB before the completer callback is called in usb_kill_urb(), resulting
in a use-after-free.
To fix this, add proper lock protection to usb_kill_urb() calls that can
possibly run concurrently with usb_kill_anchored_urbs().
Reported-by: syzbot+89bd486af9427a9fc605@syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?id=cabffad18eb74197f84871802fd2c5117b61febf
Signed-off-by: Brooke Basile <brookebasile@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200911071427.32354-1-brookebasile@gmail.com
Diffstat (limited to 'drivers/net/wireless/ath/ath9k/hif_usb.c')
| -rw-r--r-- | drivers/net/wireless/ath/ath9k/hif_usb.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/drivers/net/wireless/ath/ath9k/hif_usb.c b/drivers/net/wireless/ath/ath9k/hif_usb.c index 38f07420f4f9..860da13bfb6a 100644 --- a/drivers/net/wireless/ath/ath9k/hif_usb.c +++ b/drivers/net/wireless/ath/ath9k/hif_usb.c @@ -449,10 +449,19 @@ static void hif_usb_stop(void *hif_handle) spin_unlock_irqrestore(&hif_dev->tx.tx_lock, flags); /* The pending URBs have to be canceled. */ + spin_lock_irqsave(&hif_dev->tx.tx_lock, flags); list_for_each_entry_safe(tx_buf, tx_buf_tmp, &hif_dev->tx.tx_pending, list) { + usb_get_urb(tx_buf->urb); + spin_unlock_irqrestore(&hif_dev->tx.tx_lock, flags); usb_kill_urb(tx_buf->urb); + list_del(&tx_buf->list); + usb_free_urb(tx_buf->urb); + kfree(tx_buf->buf); + kfree(tx_buf); + spin_lock_irqsave(&hif_dev->tx.tx_lock, flags); } + spin_unlock_irqrestore(&hif_dev->tx.tx_lock, flags); usb_kill_anchored_urbs(&hif_dev->mgmt_submitted); } @@ -762,27 +771,37 @@ static void ath9k_hif_usb_dealloc_tx_urbs(struct hif_device_usb *hif_dev) struct tx_buf *tx_buf = NULL, *tx_buf_tmp = NULL; unsigned long flags; + spin_lock_irqsave(&hif_dev->tx.tx_lock, flags); list_for_each_entry_safe(tx_buf, tx_buf_tmp, &hif_dev->tx.tx_buf, list) { + usb_get_urb(tx_buf->urb); + spin_unlock_irqrestore(&hif_dev->tx.tx_lock, flags); usb_kill_urb(tx_buf->urb); list_del(&tx_buf->list); usb_free_urb(tx_buf->urb); kfree(tx_buf->buf); kfree(tx_buf); + spin_lock_irqsave(&hif_dev->tx.tx_lock, flags); } + spin_unlock_irqrestore(&hif_dev->tx.tx_lock, flags); spin_lock_irqsave(&hif_dev->tx.tx_lock, flags); hif_dev->tx.flags |= HIF_USB_TX_FLUSH; spin_unlock_irqrestore(&hif_dev->tx.tx_lock, flags); + spin_lock_irqsave(&hif_dev->tx.tx_lock, flags); list_for_each_entry_safe(tx_buf, tx_buf_tmp, &hif_dev->tx.tx_pending, list) { + usb_get_urb(tx_buf->urb); + spin_unlock_irqrestore(&hif_dev->tx.tx_lock, flags); usb_kill_urb(tx_buf->urb); list_del(&tx_buf->list); usb_free_urb(tx_buf->urb); kfree(tx_buf->buf); kfree(tx_buf); + spin_lock_irqsave(&hif_dev->tx.tx_lock, flags); } + spin_unlock_irqrestore(&hif_dev->tx.tx_lock, flags); usb_kill_anchored_urbs(&hif_dev->mgmt_submitted); } |